Susceptor system

ABSTRACT

The present invention relates to a susceptor system for an apparatus for the treatment of substrates and/or wafers, provided with a treatment chamber ( 1 ) delimited by at least two walls and with at least one heating solenoid ( 9 ); the susceptor system comprises at least one susceptor element ( 2, 3 ) delimited by an outer surface and made of electrically conducting material suitable for being heated by electromagnetic induction; the susceptor element ( 2, 3 ) is hollow; a first portion of the outer surface of the susceptor element ( 2, 3 ) is suitable for acting as a wall of the treatment chamber ( 1 ); a second portion of the outer surface of the susceptor element ( 2, 3 ) is suitable for being disposed close to the heating solenoid ( 9 ).

CROSS-RELATED TO RELATED APPLICATIONS

The present application claims priority to International Application No.PCT/IT2002/000773, filed 10 Dec. 2002, the teachings of which areincorporated herein by reference in their entirety.

The present invention relates to a susceptor system for an apparatus forthe treatment of substrates and/or wafers.

In order to produce integrated circuits, it is necessary to treatsubstrates and/or wafers; these may be made of a single material(semiconducting or insulating) or of several materials (conducting,semiconducting and insulating); the term “substrate” and the term“wafer” often refer in practice to the same thing, that is, a thinelement which is very often disc-shaped; the former term is usually usedwhen the element serves basically solely for supporting layers orstructures of semiconducting material; the second is usually used in allother cases.

There are purely thermal treatments and chemical/physical treatmentswhich involve heating.

In general, in order to grow semiconducting materials (Si, Ge, SiGe,GaAs, AlN, GaN, SiC, . . . ) epitaxially on substrates, hightemperatures are required if the quality of the material grown is to besuitable for microelectronic applications. For semiconducting materialssuch as silicon, temperatures typically of from 1000° C. to 1100° C. areused. For semiconducting materials such as silicon carbide, even highertemperatures are required; in particular, temperatures typically of from1500° C. to 2000° C. are used.

A reactor for the epitaxial growth of silicon carbide or similarmaterial therefore requires, amongst other things, a system whichgenerates heat so that these temperatures can be achieved inside areaction chamber; naturally it is desirable for the system to generateheat not only effectively but also efficiently. For these reasonsreaction chambers with hot walls are used in reactors of these types.

One of the most suitable methods of heating the walls of a reactionchamber is the method based on electromagnetic induction; an elementmade of conducting material, an inductor, and an alternating electricalcurrent (having a frequency typically of between 2 kHz and 20 kHz) areprovided, the electrical current is caused to flow in the inductor so asto generate a variable magnetic field, the element is positioned in amanner such that it is immersed in the variable magnetic field; theelectrical currents induced in the element because of the variablemagnetic field cause heating of the element by the Joule effect; aheating element of this type is known as a susceptor and can be useddirectly as a wall of the reaction chamber, if suitable materials areused.

A reactor for the epitaxial growth of silicon carbide or similarmaterial also requires the reaction chamber to be well insulatedthermally from the outside environment particularly to limit heatlosses, and to be well sealed to prevent, on the one hand, dispersal ofreaction gases contaminating the outside environment and, on the otherhand, entry of gases from the outside environment contaminating thereaction environment.

Some known susceptors suitable for use in reactors for the growth ofsilicon carbide are described briefly below.

American patent U.S. Pat. No. 5,879,462 describes a cylindricalsusceptor (of circular cross-section) which has an internal cavity(which acts as a reaction chamber), extending in a longitudinaldirection and having a substantially rectangular cross-section; thissusceptor is made entirely of silicon carbide in powder form; heatingtakes place by means which surround the susceptor and radiate aradiofrequency field.

American patent U.S. Pat. No. 5,674,320 describes a cylindricalsusceptor (of substantially elliptical cross-section) which has twointernal cavities (which act as reaction chambers) extending in alongitudinal direction and having identical and substantiallyrectangular cross-sections; this susceptor can be formed as a singlepiece or in two identical pieces each of which has an internal cavity,the pieces of the susceptor are made of graphite and are coated with alayer of silicon carbide; in the two-piece susceptor, the pieces arejoined together mechanically by means of graphite screws and areelectrically insulated from one another, in particular by the layer ofsilicon carbide; heating takes place by electromagnetic induction bymeans which surround the susceptor: the electrical currents induced inthe graphite flow all around each cavity.

American patent U.S. Pat. No. 5,695,567 describes a prismatic susceptor(of hexagonal cross-section) which has an internal cavity (which acts asa reaction chamber), extending in a longitudinal direction and having arectangular cross-section; this susceptor is made in four pieces; thepieces of the susceptor are made of graphite and are coated with a layerof silicon carbide; the pieces are joined to one another mechanically bymeans of graphite screws; two silicon carbide plates cover the upper andlower pieces of the susceptor so as to separate the side pieces from theupper and lower pieces; heating takes place by electromagnetic inductionby means which surround the susceptor; the electrical currents inducedin the graphite flow within each piece which delimits the cavity.

The object of the present invention is to provide a susceptor system foran apparatus for the treatment of substrates and/or wafers, which issuitable for being heated by electromagnetic induction by means of asolenoid, which heats the treatment chamber uniformly, effectively andefficiently and, in particular, which has a low thermal inertia but agood heating capacity, and which is also of simple construction.

This object is achieved by the susceptor system having thecharacteristics set out in independent Claim 1.

The concept upon which the present invention is based is that of using asusceptor element that is hollow and shaped in a manner such that aportion thereof is disposed close to the chamber for the treatment ofthe substrates and/or wafers (for good thermal exchange) and a portionthereof is disposed close to the solenoid (for good magnetic coupling).

Advantageous characteristics of the susceptor system according to thepresent invention are set out in the claims that are directly orindirectly dependent on Claim 1.

According to a further aspect, the present invention also relates to anapparatus for treating substrates and/or wafers having thecharacteristics set out in independent Claim 15.

Advantageous characteristics of the apparatus according to the presentinvention are set out in the claims that are directly or indirectlydependent on Claim 15.

The present invention will become clearer from the following descriptionwhich is to be considered jointly with the appended drawings, in which:

FIG. 1 is a schematic, axonometric view of a susceptor system accordingto the present invention, with some additional elements,

FIG. 2 is a schematic view showing, in section, a first embodiment ofthe susceptor system according to the present invention,

FIG. 3 is a schematic view showing, in section, a second embodiment ofthe susceptor system according to the present invention,

FIG. 4 is a schematic view showing, in section, a third embodiment ofthe susceptor system according to the present invention,

FIG. 5 is a schematic view showing, in section, a fourth embodiment ofthe susceptor system according to the present invention, and

FIGS. 6A and 6B are schematic, axonometric views of the lower wall of asusceptor system according to the present invention provided with aslide, with the slide fully inserted and with the slide removed,respectively.

The present invention will be described below with reference to theembodiments shown in the drawings but is not limited to theseembodiments.

The susceptor system according to the present invention is designedspecifically for an apparatus for the treatment of substrates and/orwafers, provided with a treatment chamber delimited by at least twowalls and with at least one heating solenoid; it comprises at least onesusceptor element having the characteristics that it is delimited by anouter surface and that it is made of electrically conducting materialsuitable for being heated by electromagnetic induction; one or more ofthe susceptor elements with these characteristics is hollow, has a firstportion of its outer surface which is suitable for acting as a wall ofthe treatment chamber, and has a second portion of its outer surfacewhich is suitable for being disposed close to the heating solenoid.

With reference to FIG. 1, the treatment chamber is indicated 1 and thesolenoid is indicated 9; in the embodiment of FIG. 1, there are twohollow susceptor elements made of electrically conducting material andindicated 2 and 3, and two non-hollow susceptor elements, indicated 4and 5; each of the susceptor elements 2, 3, 4, 5 has a first portion ofits outer surface which is suitable for acting as a wall of thetreatment chamber 1 and has a second portion of its outer surface whichis suitable for being disposed close to the heating solenoid 9.

With this arrangement, the susceptor element can be shaped in a mannersuch that a portion thereof is disposed close to the treatment chamber,which leads to a good thermal exchange, and a portion thereof isdisposed close to the solenoid, which leads to good magnetic coupling;substantially all of the induced current circulates in both of theportions since the hollow susceptor element constitutes, from anelectrical point of view, substantially a mesh and, very importantly,substantially all of the induced current (which causes heating)circulates in the immediate vicinity of the treatment chamber; by virtueof the fact that the susceptor element is hollow, its mass is notablylow and its thermal inertia is consequently notably low.

The portion of the outer surface of the susceptor element which acts asa wall of the treatment chamber must be such as to withstand hightemperatures and the aggressive environment of the treatment chamber; tofacilitate this function, the susceptor element may advantageously beprovided with thermal and chemical protection, at least in this area.

This protection may be constituted by at least one surface layer ofinert and refractory material internal to the susceptor element; this isthe case in the hollow susceptor elements 2 and 3 of the embodiments ofFIG. 2 and FIG. 3; in both embodiments, the layer extends beyond thelimits of the treatment chamber.

Alternatively, this protection may be constituted by at least one platemade of inert and refractory material adjacent the outer surface of thesusceptor element; this is the case for the hollow susceptor elements 2and 3 of FIG. 4 and FIG. 5; in both embodiments, the plate extendsbeyond the limits of the treatment chamber. Moreover, the protection mayalternatively be constituted by a combination of at least one surfacelayer of inert and refractory material internal to the susceptor elementand at least one plate made of inert and refractory material adjacentthe outer surface of the susceptor element.

Since electrical currents (induced by the solenoid) flow through thesusceptor elements, it may be advantageous in some cases for the inertand refractory material of the layer and/or of the plate also to beelectrically insulating so as to prevent electrical sparks in thetreatment chamber and/or electrical leakages.

A substance which is particularly suitable for producing susceptorelements made of conducting material is graphite; however, graphitecannot withstand the typical environment of a treatment chamber andtherefore has to be protected by material that is more resistant fromthe chemical and thermal points of view. Protection of the graphite isstrictly necessary only in the areas that are adjacent the chamber, butit may sometimes be more convenient and/or advantageous to producecomplete protections or at least beyond the necessary minimum.

A compound suitable for producing the protective layer and/or the plateis silicon carbide; however, if the chamber is also used for theepitaxial growth of silicon carbide, it is preferable to use even moreresistant compounds such as niobium carbide, boron carbide, or tantalumcarbide; amongst other things, the latter two compounds also have theproperty of being electrical conductors.

Other compounds usable to produce the protective layer and/or the plateare some nitrides; amongst these, silicon nitride, aluminum nitride and,in particular, boron nitride may be mentioned. Nitrides are to be usedwith great care if, for example, silicon carbide is to be treated in thechamber; in fact, if nitrogen atoms should become detached from thecoating layer, they would dope the silicon carbide.

If the layer and/or the plate is to be made of electrically conductingmaterial, tantalum carbide or boron carbide, for example, may be used.

It should be explained that the above-mentioned chemical substances havephysical properties which depend on their allotropic form and also onthe production process; for example, carbon, silicon carbide, and boronnitride have more than one stable allotropic form, with quite differentphysical properties; again, for example, with graphite it is possible toproduce materials with good thermal and electrical conductivity andmaterials with poor thermal and electrical conductivity; finally, theaddition of chemical compounds to a material can modify some of itsphysical properties.

The protective layer may be produced basically in two ways: by chemicalreaction, or by physical application. For example, a layer made of acarbide can generally be produced more easily by chemical reaction on agraphite piece. There are companies that are specialized in producingsuch layers.

As far as the thickness of the protective layer is concerned, forsilicon carbide, it may be, for example, 100 m and for tantalum carbide,for example 20 m; the thickness to be used may depend, amongst otherthings, on the properties of the material and on the function required.

Advantageously, the susceptor element may be made hollow so as to haveat least one hole, preferably a through-hole, which extends in alongitudinal direction; the induced currents are thus necessarilyconfined to the peripheral region and therefore necessarily flow veryclose to the treatment chamber; this is the case in all of theembodiments shown in the drawings, in which the susceptor element 2 hasa through-hole 21 and the susceptor element 3 has a through-hole 31. Infact, the number of through-holes for each susceptor element may begreater than one, but the effect does not change substantially.

All of the embodiments shown in the drawings comprise two hollowsusceptor elements 2, 3; a first portion of the outer surface of one ofthe two susceptor elements and a first portion of the outer surface ofthe other of the two susceptor elements are suitable for acting as anupper wall and as a lower wall of the treatment chamber 1, respectively;a second portion of the outer surface of one of the two susceptorelements and a second portion of the outer surface of the other of thetwo susceptor elements are suitable for being disposed close to theheating solenoid 9; the advantages are thus doubled quantitatively.

Two walls, if they are suitably shaped, are sufficient to delimit atreatment chamber completely (at the top and at the bottom). In all ofthe embodiments shown in the drawings, however, it is preferred furtherto include two susceptor elements 4, 5 which are suitable for acting asa right-hand side wall and as a left-hand side wall of the treatmentchamber 1, respectively.

Even when the susceptor system according to the present invention isconstituted by four susceptor elements, as in all of the embodimentsshown in the drawings, its construction is nevertheless very simple; infact, the walls can simply be placed close together and inserted in asuitable compartment, as shown in FIG. 1; the structure of the susceptorsystem may, however, be rendered firmer by means of simple longitudinalribs and/or grooves for the mutual coupling of the elements.

These side susceptor elements may be made of electrically insulatingmaterial which, in addition, is inert and refractory, they can thuswithstand the high temperatures and the aggressive environment of thetreatment chamber and, at the same time, can prevent electrical leakagesof the currents which circulate in the hollow susceptors and reduce thelikelihood of electrical sparks.

A compound which is particularly suitable for the production of the sidesusceptor elements is silicon carbide; in this case, moreover, theyconduct heat well and thus achieve good passive heating.

Another compound which is particularly suitable for producing the sidesusceptor elements is boron nitride; in this case also, they conductheat well and thus achieve good passive heating; in fact this compoundhas a hexagonal allotropic form with physical properties similar tothose of graphite and a cubic allotropic form with physical propertiessimilar to those of diamond; one or other allotropic form can beproduced, according to the production process.

Alternatively, the side susceptor elements may be made of electricallyconducting material and contribute actively to the heating of thetreatment chamber. In this case also, the portion of their surface whichis adjacent the treatment chamber must be such as to withstand the hightemperatures and the aggressive environment of the treatment chamber; tofacilitate this function, these susceptor elements may advantageously beprovided with thermal and chemical protection, at least in this area.

In the embodiments of FIG. 3 and of FIG. 4, the side susceptor elements4 and 5 are provided with protection constituted by at least one surfacelayer of inert and refractory material internal to the susceptorelement.

In the embodiment of FIG. 5, the side susceptor elements 4 and 5 areprovided with protection constituted by at least one plate of inert andrefractory material adjacent the surface of the susceptor element.

According to how the susceptor elements 2 and 3 are made, the protectionfor the side susceptor elements may be made of electrically conductingor electrically insulating material.

If the side susceptor elements are not used as a main source of heatingof the treatment chamber, it is simpler and therefore advantageous ifthey are not hollow; in this case, the side susceptor elements are muchsmaller than the upper and lower susceptor elements; this is the case inall of the embodiments shown in the drawings.

An optimal geometrical solution, which is common to all of theembodiments shown in the drawings, consists of hollow susceptor elementswhich extend substantially uniformly in a longitudinal direction andwhich have cross-sections having the external shape substantially of asegment of a circle or ellipse, and of non-hollow susceptor elementswhich extend substantially uniformly in the longitudinal direction andwhich have cross-sections of substantially rectangular or trapezoidalshape.

A susceptor system of this type is typically usable in an apparatus ofthe type suitable for treating substrates and/or wafers; this is afurther aspect of the present invention.

The apparatus according to the present invention will be described belowwith non-limiting reference to FIG. 1.

The apparatus according to the present invention is provided with atreatment chamber delimited by at least two walls and comprises,essentially a susceptor system with a hollow susceptor element adjacentthe treatment chamber and at least one solenoid which is wound aroundthe susceptor system and the treatment chamber and is suitable forheating the susceptor system by electromagnetic induction.

In FIG. 1, the treatment chamber is indicated 1; the susceptor system iscomposed of four susceptor elements, indicated 2, 3, 4, 5, of which two,that is the elements 2 and 3, are hollow; the solenoid is indicated 9.

Advantageously, the susceptor system extends in the apparatus in thelongitudinal direction and the external shape of the cross-section ofthe susceptor system according to the present invention is substantiallyuniform in the longitudinal direction and is substantially circular orsubstantially elliptical; the susceptor system is in fact thus easy toproduce and can easily be coupled well with a solenoid for heating it.

The shape of the cross-section of the treatment chamber of theapparatus, is also advantageously substantially uniform in thelongitudinal direction; practical implementation is in fact thussimplified.

In known reactors, the cross-section of the chamber reduces in thelongitudinal direction to compensate for the reduced concentration ofthe precursors. Instead, the present invention solves this problem bycausing the substrates or wafers to rotate and using a high flow ofreaction gas; this high gas-flow also has the advantage of effectivelyand quickly removing any solid particles from the reaction chamber.

The average width of treatment chamber, is preferably at least threetimes, even more preferably at least five times, the average height ofthe treatment chamber; the heating of the treatment chamber is in factthus due to a greater extent to the walls of the hollow susceptorelements.

The apparatus according to the present invention may advantageouslycomprise a first structure 7 which surrounds the treatment chamber 1 andthe susceptor system 2, 3, 4, 5 and which is constituted, substantially,by a tube of refractory and thermally insulating material which extendsin a longitudinal direction; in this case, the solenoid 9 is woundaround the first structure 7.

The apparatus according to the present invention may also advantageouslycomprise a second, hermetic structure 8 suitable for surrounding thefirst structure 7; in this case, the solenoid 9 is also wound around thesecond structure 8.

These structures may be formed as single pieces or in several pieces,suitably joined together.

If the susceptor system of the apparatus has walls provided withthrough-holes, as in the embodiments shown in the drawings, theapparatus may advantageously comprise means suitable for causing atleast one gas-flow to flow within at least one of the holes; thegas-flow may serve to remove any particles which are detached from theinternal walls of the hole; the gas-flow may also serve to modify thetemperature of the susceptor system slightly; argon or, more generally,an inert gas, is suitable in particular for the former function;hydrogen, for example, is suitable in particular for the latter functionand, more particularly, for cooling.

The apparatus according to the present invention may advantageouslycomprise a slide, indicated 6 in FIG. 6A, mounted within the treatmentchamber, and suitable for supporting at least one substrate or at leastone wafer; the slide can slide in guided manner in the longitudinaldirection; operations to insert and remove substrates or wafers are thusfacilitated; in fact the substrates or wafers are manipulated outsidethe treatment chamber and are inserted and removed by the movement ofthe slide.

In practice, it is convenient to arrange for the susceptor system (inthe embodiment of FIG. 6, the lower susceptor element 3) to have aguide, indicated 32 in FIG. 6B, which is suitable for receiving theslide, indicated 6 in FIG. 6A, and which extends in the longitudinaldirection in a manner such that the slide can slide along the guide. Inthe embodiment of FIG. 6, the guide 32 is formed entirely within thesusceptor element 3 and the slide 6 has a flat upper surface that issubstantially aligned with the flat upper surface of the susceptorelement 3; the effective cross-section of the treatment chamber 1 isthus substantially rectangular and regular (as if the slide 6 were notprovided).

To achieve a more uniform treatment of the substrates or wafers, theslide may comprise at least one disc suitable for supporting at leastone substrate or at least one wafer and may be provided with a recessfor housing the disc rotatably; in the embodiment of FIG. 6, the slide 6comprises a single disc, indicated 61 in FIG. 6A, and is provided with acorresponding recess, indicated 62 in FIG. 6A, for housing it.

The apparatus according to the present invention can be used, with theaddition of further components, as a reactor for the epitaxial growth ofsilicon carbide or similar material on substrates.

Silicon carbide is a semiconducting material which is very promising butalso very difficult to handle; most of the characteristics set out aboveare designed particularly for this use and for this material.

The apparatus according to the present invention may also be used, withthe addition of further components, as apparatus for thehigh-temperature thermal treatment of wafers.

1. A susceptor system for an apparatus for the treatment of substratesand/or wafers, provided with a treatment chamber (1) delimited by atleast two walls and with at least one heating solenoid (9), comprisingat least one susceptor element (2, 3) delimited by an outer surface andmade of electrically conducting material suitable for being heated byelectromagnetic induction, characterized in that the at least onesusceptor element (2, 3) is hollow so as to have at least one throughhole which extends in a longitudinal direction, and in that a firstportion of the outer surface of the at least one susceptor element (2,3) is suitable for acting as a wall of the treatment chamber (1), and inthat a second portion of the outer surface of the at least one susceptorelement (2, 3) is suitable for being disposed close to the heatingsolenoid (9).
 2. A susceptor system according to claim 1, in which theat least one susceptor element (2, 3) is provided with thermal andchemical protection at least on the first portion of the outer surface.3. A susceptor system according to claim 2 in which the protection isconstituted by at least a surface layer of inert and refractory materialinternal to the at least one susceptor element (2, 3).
 4. A susceptorsystem according to claim 2 in which the protection is constituted by atleast one plate of inert and refractory material adjacent the outersurface of the at least one susceptor element (2, 3).
 5. A susceptorsystem according to claim 2 in which the protection is constituted by acombination of at least one surface layer of inert and refractorymaterial internal to the at least one susceptor element (2, 3) and atleast one plate of inert and refractory material adjacent the outersurface of the at least one susceptor element (2, 3).
 6. A susceptorsystem according to claim 3, in which the inert and refractory materialis also electrically insulating.
 7. A susceptor system according toclaim 1 comprising two hollow susceptor elements (2, 3) in which a firstportion of the outer surface of one (2) of the two susceptor elementsand a first portion of the outer surface of the other (3) of the twosusceptor elements are suitable for acting as an upper wall and as alower wall of the treatment chamber (1), respectively, and in which asecond portion of the outer surface of one (2) of the two susceptorelements and a second portion of the outer surface of the other (3) ofthe two susceptor elements are suitable for being disposed close to theheating solenoid (9).
 8. A susceptor system according to claim 7,further comprising two susceptor elements (4, 5) made of electricallyinsulating and also inert and refractory material and suitable foracting as a right-hand side wall and as a left-hand side wall of thetreatment chamber (1), respectively.
 9. A susceptor system according toclaim 7, further comprising two susceptor elements (4, 5) made ofelectrically conducting material and suitable for acting as a right-handside wall and as a left-hand side wall of the treatment chamber (1),respectively.
 10. A susceptor system according to claim 9, in which theside susceptor elements (4, 5) are provided with thermal and chemicalprotection at least on the portion of their surface that is adjacent thetreatment chamber (1).
 11. A susceptor system according to claim 8, inwhich the side susceptor elements (4, 5) are not hollow.
 12. A susceptorsystem according to claim 1, in which at least one of the hollowsusceptor elements (2, 3) extends substantially uniformly in alongitudinal direction and has a cross-section having the external shapesubstantially of a segment of a circle or ellipse.
 13. A susceptorsystem according to claim 1, in which at least one of the non-hollowsusceptor elements (4, 5) extends substantially uniformly in alongitudinal direction and has a cross-section having a substantiallyrectangular or trapezoidal external shape.
 14. Apparatus of the typesuitable for treating substrates and/or wafers, provided with atreatment chamber (1) delimited by at least two walls, characterized inthat it comprises a susceptor system (2, 3, 4, 5) according to claim 1adjacent the treatment chamber (1) and at least one solenoid (9) whichis wound around the susceptor system (2, 3, 4, 5) and the treatmentchamber (1) and is suitable for heating the susceptor system byelectromagnetic induction.
 15. Apparatus according to claim 14 in whichthe susceptor system (2, 3, 4, 5) extends in a longitudinal direction,and in which the external shape of the cross-section of the susceptorsystem (2, 3, 4, 5) is substantially uniform in the longitudinaldirection and is substantially circular or elliptical.
 16. Apparatusaccording to claim 14, in which the treatment chamber (1) extends in alongitudinal direction and in which the shape of the cross-section ofthe treatment chamber (1) is substantially uniform in the longitudinaldirection.
 17. Apparatus according to claim 16, in which the averagewidth of the treatment chamber (1) is at least three times, preferablyat least five times the average height of the treatment chamber (1). 18.Apparatus according to claim 14, comprising a first structure (7) whichsurrounds the treatment chamber (1) and the susceptor system (2, 3, 4,5) and which is constituted substantially by a tube of refractory andthermally insulating material which extends in a longitudinal direction,and in which the solenoid (9) is wound around the first structure (7).19. Apparatus according to claim 18, comprising a second, hermeticstructure (8) suitable for surrounding the first structure (7), and inwhich the solenoid (9) is also wound around the second structure (8).20. Apparatus according to claim 16, comprising means for causing atleast one gas-flow to flow in at least one through-hole (21, 31) of thesusceptor system (2, 3, 4, 5).
 21. Apparatus according to claim 14,comprising a slide (6) mounted inside the treatment chamber (1) andsuitable for supporting at least one substrate or at least one wafer,the slide (6) being slidable in guided manner in the longitudinaldirection.
 22. Apparatus according to claim 21 in which the susceptorsystem (2, 3, 4, 5) has a guide (32) which is suitable for receiving theslide (6) and which extends in the longitudinal direction so that theslide) can slide along the guide (32).
 23. Apparatus according to claim21 in which the slide (6) comprises at least one disc (61) suitable forsupporting at least one substrate or at least one wafer, and is providedwith a recess (62) suitable for housing the disc (61) rotatably. 24.Apparatus according to claim 15, characterized in that it is a reactorfor the epitaxial growth of silicon carbide or similar material onsubstrates.
 25. Apparatus according to claim 15, characterized in thatit is an apparatus for the high-temperature thermal treatment of wafers.